School officials placed Puesta del Sol Elementary in the desert town of Victorville on lockdown Wednesday morning after a fight broke out among a group of parents.

The San Bernardino County sheriff's department says witnesses told deputies several mothers were involved in an argument and it got physical in a field near the ceremony. Several men then jumped into the fray and the incident turned into a brawl.

A deputy later arrested two people on suspicion of being a disruptive presence at a school. Witnesses said they were the main instigators. In all, 20 adults were identified in the brawl. A school district official said there could be more arrests.

No injuries were reported.

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